I'm having some trouble getting to the data I want to in the JSON file. Here is a shortened version of the output from my console:
{
AUD = {
15m = "125.15547";
24h = "124.74";
buy = "121.0177";
last = "125.15547";
sell = "123.44883";
symbol = "$";
};
BRL = {
15m = "120.34";
24h = "120.34";
buy = "120.34";
last = "120.34";
sell = "120.34";
symbol = "R$";
};
CAD = {
15m = "129.08612";
24h = "131.07";
buy = "128.66227";
last = "129.08612";
sell = "129.08612";
symbol = "$";
};
}
I'm trying to parse the file using the built in JSON parsing library. Here is the parser in my viewDidLoad
method:
_tickerArray = [NSMutableArray array];
NSURL *tickerDataURL = [NSURL URLWithString:@"https://blockchain.info/ticker"];
NSData *jsonData = [NSData dataWithContentsOfURL:tickerDataURL];
NSError *error = nil;
NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
NSLog(@"%@", dataDictionary);
NSArray *ar = [NSArray arrayWithObject:dataDictionary];
for (NSString *key in [dataDictionary allKeys]) {
for (NSDictionary *dict in ar) {
TickerData *t;
t.currency = [dict objectForKey:key];
t.symbol = [dict objectForKey:@"symbol"];
t.last = [dict objectForKey:@"last"];
[_tickerArray addObject:t];
}
}
I want to store the currency code (like AUD or BRL
) into t.currency
along with some of the other data contained in the currency dictionary but now my app is crashing.
Error code:
NSInvalidArgumentException', reason: '*** -[__NSArrayM insertObject:atIndex:]: object cannot be nil
None of the objects seem to get added to the _tickerArray
Help?
EDIT: Getting the keys to display with the proper data populating other fields:
NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
NSLog(@"%@", dataDictionary);
for (NSString *key in [dataDictionary allKeys]) {
NSDictionary *dic=[dataDictionary objectForKey:key];
TickerData *t=[[TickerData alloc] init];
t.currency = key;//EDITED
t.symbol = [dic objectForKey:@"symbol"];
t.last = [dic objectForKey:@"last"];
[_tickerArray addObject:t];
}
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